The present invention relates to a storage type hexagonal socket wrench and, more particularly to a hexagonal socket wrench having one set of hexagonal socket wrench elements in a variety of sizes for selective use.
This invention is derived from an improvement made on a conventional storage type screw driver. Please refer to the illustration of the the conventional storage type screw driver shown in FIG. 1. The screw driver comprises a handle (1), a driving shaft (2), a nut (3), a washer (4), a back seat (5), a locating ring (6), a rotatable storage wheel (7), a front seat (8), a spring (9), a locating block (901), a bolt (902), and one set of driving elements (101), (102), . . . etc., wherein a control switch (201) is provided between the handle (1) and the driving shaft (2) to control forward or backward, i.e. clockwise or counterclockwise rotation. The driving shaft (2) comprises a cylindrical portion (202) at the front having notches (203) and (204) therein, as illustrated in FIGS. 3 and 4, and the driving shaft (2) also comprises a locating hole (205) made at the rear portion. The nut (3) has a cylindrical outer configuration, comprising an inner thread (301), and a reduced round hole (302) at the rear end for insertion therethrough of the driving shaft (2). A locating pin (206) is set in the locating hole (205) of the driving shaft (2) with a small portion protruding therebeyond to prevent the nut (3) from breaking away.
The back seat (5) includes a tube-like extension (502) extending rearwardly which has a hexagonal opening (501); therein, and thread (503) thereon. The driving shaft (2) is arranged to pass through the washer (4) and the hexagonal opening (501) of the back seat (5) to further be connected with the back seat (5) by means of threaded engagement of the nut (3) with the thread (503) of the tubular extension (502). The back seat (5) comprises a revolving axle (504) at the front-central portion having a bolt hole made therein at the middle portion (not illustrated in the drawing). The locating ring (6) comprises a convex outer and concave contour similar to the back seat (5), rotatable storage wheel (7) and the front seat (8), having a round hole at the inner portion including a notch (602). The rotatable storage wheel (7) comprises an axial hole (701) and 6 other holes (702), (703), (704), (705), (706), and (707) equidistantly arranged around the axial hole (701) for respectively receiving the driving elements (101), (102),
The portions (103) and (104) at the rear end (referring to the element (101) as illustrated in FIG. 1) respectively match with the notches (203) and (204) of the driving shaft (2) wherein the protruding portion (104) and the cylindrical body of the driving element forms a notch (105). The front seat (8) comprises a tubular body (802) at the front having an axially extending round hole (801) therein, another round hole (803) arranged at the back side for receiving the spring (9) and locating block (901), and a hole (804) located at the back center for insertion therethrough of the bolt (902) to further threadedly engage with the bolt hole of the revolving axle (504) of the back seat (5) so as to complete the assembly as shown in FIG. 2.
While the driving elements (101), (102), . . . are stored in the respective holes (702), (703), . . . of the rotating wheel (7), the notch (105) of each element is retained by the locating ring (6) to prevent the element from moving away. To operate, the driving shaft (2) is pulled backward to the limit, and the rotating wheel (7) is revolved to align the preferred driving element with the driving shaft (2), i.e. to let the protruding portions (103) and (104) of the preferred driving element be respectively set in the notches (203) and (204) of the driving shaft (2). After fixation of the preferred driving element with the driving shaft (2), the driving shaft (2) is pushed ahead to force the preferred driving element away from the rotatable wheel (7) to further protrude beyond the tubular body (802) of the front seat for screw-driving application. When another size of driving element is required, the driving shaft (2) is pulled backward to the limit, then the procedures are followed as above-described. Further, the rotatable wheel (7) may be marked with the respective sizes of the driving elements on the outer surface of the respective holes (702), (703), . . . etc., to facilitate selection.
Although this storage type screw driver can provide a plurality of driving elements for alternative application, it is not practical for application as a hexagonal socket wrench because of the below described disadvantages.
&lt;A&gt; The rotation of the driving element (101), (102), . . . etc., is provided through the engagement of the protruding portion (103) with respective notch (203). This structure is not strong enough for driving large size hexagonal socket wrench elements.
&lt;B&gt; The driving element (101), (102), . . . which comprises a protruding portion (103), (104) requires a complicated process to produce. In consequence, the manufacturing cost is expensive.
&lt;C&gt; The driving lever (2) which comprises front notches (203) and (204) also requires a complicated process to produce, so that the manufacturing cost is high.
&lt;D&gt; While assembling, each driving element (101), (102), . . . should be properly arranged to let the notch (105) be retained at the round hole (601) of the locating ring (6). Therefore, it is difficult to assemble the component parts.
&lt;E&gt; It provides a short torque arm which is not practical for the application of the heavy torque force required to drive a hexagonal socket wrench element. The handle and the driving lever shaft are arranged in an L-shaped configuration, to which the torque force is more difficult to apply.
The present invention is directed to making use of the advantage of a storage type screw driver to carry a variety of driving elements for alternative application with an improvement being made on the structure for application of bigger torque force to drive a hexagonal socket wrench.